POOR CUSTOMER SERVICE AND ***********

I rest my case with MTN. Maybe someone can assist. I tried to speak to almost everyone at MTN from last year October till to date, however no one bother to solve my query. From last year October MTN stopped to debit my account. I phoned them but no one is giving any explanation this problem. Around December I made arrangement with them to debit the contract money which is now R1287. However instant of debiting this amount they only debited R287 which I noticed today and don't understand why . When i call Wendy (MTN customer service) was just so rude. Presyton Webster (MTN Supervisor) promised to call me back. But till now no one called me back. I have been with this organization for more than 15 years but I think is time to part away with them. I'm in arrears with MTN because of their negligence and ***********. I just don't know who to talk to at this company because everyone seem not to care.